Power-driven oscillating eraser



Dec. 19, 1950 P. c. HUTTON POWER-DRIVEN OSCILLATING ERASER 2 Sheets-Sheet 1 Filed NOV. 20, 1947 Fig. 2.

Paul 6. Hut/0n INVENTOR.

Patented Dec. 19, i950 UNHTED STATES IhATENT OFFICE 2,534,773 7 PQWER-DRIVEN OSCILLATING EaAsER Paul C. Hutton, Washington, D. C. Application November 20, 1947, Serial No. 787,077

(01. izose) '7 Claims.

' Another object is to facilitate the rapid interchange of erasers in a mechanical erasing device should one become worn through use, and to enable fresh and unused erasers easily to be substituted for any which have become unserviceable for any reason whatsoever.

A further object is to enable the driving spring of a mechanical eraser easily to be wound with a minimum amount of effort on the part of the user.

A still further object is to place within the grasp of the user control mechanism by which the oscillations of the eraser may be arrested as soon as the erasing operation has been completed, and also to reduce the speed of the oscillatory motion of the eraser to avoid a too rapid deenergization of the spring.

\ The above and other objects may be attained by employing this invention which embodies among its features an elongated tubular. body, a

rocker arm supported'in saidbody to oscillate about an axis which lies perpendicular to the longitudinal axis of the body, an eraser supported on the rocker arm for movement beyond one end oi" the tubular body and means at the opposite end of the tubular'body for imparting oscillatory motion to the rocker arm.

Other features include manually actuated means on the tubular body near the end adjacent the'eraser for arresting oscillatory motion of the rocker arm, a governor on the body to reduce the v eraser thereto, and a spring actuated drive motor including a spring driven winding drum upon which an eraser actuating tape. is wound, a zigzag cam track extending longitudinally of the tape-, a'nd means coupling the end of the rocker arm're'xnotefrom the eraser to the tape forentory motion of the rocker is produced as the tap is wound upon the drum. In the drawings:- Figure l is a perspective view of an eraser embodying features of this invention,

Figure '2- is a broken longitudinal sectional view on a somewhat enlarged scale through the eraser illustrated in Figure 1,

Figure 3 is a View similar to that of Figure --2 taken substantially in a plane perpendicular of Figure 2,

Figure 4 partially in section on an enlarged scale of lower end of the eraser,

Figure 5 is a fragmentary perspective viewon an enlarged scale of the upper end of the eraser, Figure 6 is a horizontal sectional view taken substantially along the line 6-4 of Figure 2, 3

Figure 7 is a transverse sectional view taken is a fragmentary perspective view the "substantially along the line 1-1 or Figure 6,

Figure 8 is afragmentary plan viewof the driving tape illustrating the zig-zag cam track therein.

Figure 9 is a perspective view of the rocker arm,

Figure 10 is a side view of the rocker arm pivot.

Referring to the drawings in detail, this iiirproved eraser embodies an elongated tubular body it provided at one end with diametrically arranged longitudinally extending arms l2 which are pierced adjacent their ends, remote from the body II) with aligning rectangular openings ['4 for a purpose to be more fully hereinafter explained. Entering the end of the body remote from the arms I? at diametrically opposite points are elongated slots [5 which are arranged in axial alignment with the arms l2. Formedin the body adjacent the end containing the slots l6 and extending through the wall of the body along an axis perpendicular to the plane of the axes of" the slots I6 is an opening if; provided adjacent its lower edge with an inturned cam 20, the purpose of which will be more fully hereinafter explained.

Formed in the body intermediate its endsare pairs of diametrically opposed aligned openings 22, 24' and 26, and extending between the openings on each side of the body are longitudinal slots 28. The axes of the openings 22, 24 and 26 lie in a longitudinal plane which lies perpendicular to the axes of the openings in and formed in the body adjacent the end carrying the arms 12 is a transverse slot 30 which aligns axially with an indentation 32 which opens into the interior of the body. Extending transversely through the body and ofiset to one side of the longitudinal axis thereof are spaced, parallel guide bars 34, the outer ends of which project through the body and are headed over to form stops for a sliding sleeve to be more fully hereinafter described. These guide bars 34 are arranged in spaced parallel relation and serve as guides for the oscillating arm to be described hereinafter.

Extending transversely through the body I is a pivot pin 36 which comprises a cylindrical stem 38 having adjacent opposite ends cylindrical heads 40 and 42. A conical portion 44 is formed at the junction of the stem 38 and the head 40, and formed on the head 42 on the side remote from the stem 38 is a conical portion 46, the convergent end of which terminates in a cylindrical extension 48 of a length sufficient to accommodate the thickness of the wall of the tubular body I0. Extending longitudinally from the head 40 in the direction opposite the stem 38 is a cylindrical portion 50 which, like the portion 48, is of a length sufiicient to accommodate the thickness of the wall of the tubular body l0, and formed at the end of the extension 50 is a conical portion 52 which terminates at its larger end in a cylindrical portion 54. The pivot pin 36 is provided at its extreme opposite ends with heads 56 which, as illustrated in Figure 2, lie on the outside of the cylindrical bod I0 to serve as thumb pieces by which the pivot may be shifted along its longitudinal axis and transversely of the tubular body I0. By shifting the pivot to the left when viewed as in Figure 2 it will be obvious that the extensions 48 and 50 will be moved to align with the'wall of the body I0 so that the pivot may be shifted longitudinally through the slots 28 into a position to align with the different pairs of openings 22, 24 and 26. When the pivot has been brought into align- .ment with any group of the above mentioned mentin the body.

Supported on the pivot'36 within the tubular body I0 is a rocker arm 58 which is provided intermediate its ends with longitudinally spaced transversely extending openings 60, 62 and 64 which align respectively with the openings 22, 24 and 26 in the body I0. This rocker arm is movable between the guides 34, and extending longitudinall through the rocker arm between the openings 60, 62 and 64 are longitudinal slots ,66. The openings 60, 62 and 64 are of a size to receive the cylindrical portion 40 of the pivot pin 36 and the slots 66 are of a width sufficient to accommodate the stem 38 of the pivot pin 36. It will thus be seen that when the pivot pin 36 is shifted longitudinally of the tubular body I0 it also may be shifted longitudinally through the rocker arm 58 in order to regulate the swin of the eraser which is carried by the rocker arm without in any way altering the length of motion of the opposite end of the rocker arm.

-Riveted or otherwise fixed to one end of the rocker arm 58 is an actuating arm 68 which terminates adjacent its upper end in a reduced neck "I0 on the upper end-of which is fixed an angularly extending enlarged head I2.

Pivotally supported adjacent the end of the rocker arm 58 remote from the actuating arm 68 to swing about an axis which lies perpendicular to the longitudinal axis of the rocker arm is an eraser carrier I4. This eraser carrier constitutes a straight bar of metal or the like, the pivot point of which is located midway between opposite ends, and riveted or otherwise fixed to the arm 58 between the eraser carrier I4 and the arm is a retaining spring 16, which extends beyond the end of the rocker arm 58 and carries a latch pin I8 which is adapted t enter sockets formed in the adjacent side of the eraser carrier 14. The extreme end of the latch spring 16 is curved outwardly as at 82 to facilitate the withdrawal of the pin I8 from a socket 80 to permit the carrier 14 to be swung around the axis of its pivot. A sleeve or socket member 84 is fitted over each end of the eraser-carrier l4, and is frictionally held thereon so that it may be removed and another substitued therefor when conditions so require. Each sleeve 84 is equipped at its end remote from the carrier I4 with any suitable erasing substance 86 such as fiber glass or the like.

Riveted or otherwise attached to the exterior of the cylindrical body I0 adjacent the end containing the opening I8 is a leaf spring 88 having an angularly extending end 90 having covergent sides as illustrated in Figure 4 which when the spring is extended as illustrated lies adjacent one side of the rocker arm 58 to hold it against oscillatory motion about the pivot 36. When,however, pressure is applied to the exterior of the Spring 08, the tongue or arm 90 will ride against the cam 20 through the opening I8 so that it may be forced upwardly to lie substantially parallel with the inner side of the wall of the tubular member I0 and clear the rocker arm 58 so as to permit oscillation thereof. It will thus be seen that by pressing the finger against the spring 88, or releasing pressure on the spring the oscillation of the rocker arm 58 may be controlled.

Mounted for longitudinal sliding movement on the tubular body I0 between the heads of the guide pins 34 and the slotted end of the body is a sleeve 92 which is provided with a longitudinal slot 94 which opens through one end to accommodate the sprin 88, and this sleeve serves to close the slots I6 under normal operating conditions. The sleeve, however, may be slid upwardly on the body I0 until the end thereof remote from the eraser 86 engages the heads of the cross pins 34, at which time the slots I6 will be cleared to permit the eraser carrier 14 to be swung about its pivot so as to present a new erasing surface to a position for operation. The sleeve 92 may then be returned to the position illustrated in Figures 1, 2 and 3.

Mounted in the rectangular openings I4 are the squared ends of a shaft 96 upon which a pair of spaced guide disks 98 are mounted. These guide disks are held in spaced parallel relation by a cylindrical drum I00, and fixed to the shaft 96 is one end of a spiral spring I02, the opposite end of which is fixed to the inner side of the drum I00 so that when the drum is rotated in one direction, the spring will be placed under tension. Fixed to the drum I00 is one end of a tape I04 which as illustrated in Figure 8 is provided with a longitudinally extendin zig-zag cam track I06. In the preferred form of the invention, the cam track I06 constitutes a slot cut through the tape I04 through which projects the neck 10 adjacent the head 12 of the operating arm 68 of the rocker arm 58. This tape I04 is preferably so tensioned that it will tend to roll upon itself,

and fixed to the end of the tape remote from that which is connected to the drum I is a magazine reel I08 having extending therethrough an axle IIO, the ends of which project well beyond opposite sides of the reel to form finger grips by means of which the tape may be drawn and unreeled from the drum in order to tension the spring I02. Opposite ends of the cam track I 06 open into enlarged openings I and IN the purpose of which will more fully hereinafter appear.

Fixed to the tubular body I0 adjacent the arms I2 is a bracket I I2 which carries at its upper end a laterally projecting arm II4, the opposite side edges of which are provided with upturned guide flanges I I6 which serve as guides for the tape I 04. The end edges of the guide flanges II6 remote from the reel or drum I00 are provided with notches H8 in which the shaft I I0 is received as illustrated in Figure 1'.

Extending laterally from the lower end of the bracket H2 is an arm I provided adjacent opposite side edges with upturned supporting arms I22 which are pierced with aligning openings I24 for the reception of a longitudinally moving piston rod I26. A cylinder I28 is fixed to the arm I20, and fixed to the piston rod and operable within the cylinder I28 is a piston I30. The opposite ends of the cylinder are provided with aligning openings I32 through which the piston rod I26 extends, and fixed to opposite ends of the piston rod are the arms I34 of a U-shaped piston actuating member I36. Pivotally connected to the actuating membe I36 midway between the arms I34 is one end of an oscillating arm I38 which as illustrated in Figure 2 projects through a transverse slot in the bracket II2 which registers with the slot in the tubular body I0. This lever I38 is provided intermediate its ends with a slot I40 for the reception of the neck I0 on the actuating arm 68 of the rocker arm 58, and the end of the lever I38 remote from that which is connected to the frame I36 is pointed as at I42 to seat in the indentation 32 as will be readily understood upon reference to the drawings. It will thus be seen that the lever I38 will be rocked about its junction with the indentation 32 as the rocker arm 58 is driven through the medium or" the cam track I06 in the tape I04. It will also be understood that the movements of the piston I30 within the cylinder I28 will serve to compress the air in opposite ends of the cylinder, thus forming a pneumatic governor by means of which the speed of oscillation of the rocker arm 58 will be retarded.

In use, the operator in order to energize the spring I02 grasps the opposite ends of the shaft IIO of the reel I08 and by turnin his wrist lifts the tape or ribbon I04 so that the head I2 will pass through the opening I05 so as to enable the tape I04 to be unwound from the drum I00 without oscillating the rocker arm 58. When the ribbon or tape I04 has been fully unwound from the drum the tubular body I0 is tilted in a reverse direction to cause the head I2 to enter the opening I0'I in the ribbon I04 so that as the ribbon again tends to wind about the drum I00 under the influence of the spring I02 the cam track I06 therein will re-engage the neck I0 of the actuating arm 68 beneath the head I2. Obviously the unwindin of the tape I04 from the drum I00 will cause the spring I02 to wind about the shaft 96 and after the tape has been pulled out to its fullest extent, the spring will be fully wound and will so remain until pressure is applied to the spring 88, so as to cause the tongue 90 to move into a position to disengage'the rocker arm 58. Since the tape I04 is of the type that is selfwinding it is obvious that by moving the magazine or reel I08 toward the drum I00, the tape will wind about the shaft H0 and hence becomes stored in the magazine. The device is now ready for use and when it is desired to set the eraser in operation, pressure is applied to the sprin 88, thus causing the tongue 90 to fold upwardly through contact with the cam 20 so as to clear the rocker arm 58 and permit the arm to oscillate under the influence of the movement of the tape as it is wound upon the drum I00 under the influence of the spring I02. Obviously, the actuating arm 68 will oscillate about the axis of the pivot 36 as the opposite walls of the zig-zag cam track I06 contact opposite sides of the neck 10. By shifting the pivot pin 36 into thediiiterent groups of openings in the tubular body I0 and the rocker arm 58, it is obvious that the length of stroke of the eraser may be governed. When it is desired to replace a Worn eraserlwith a new one, it is only necessary to remove the eraser carrying socket 84 from the eraser carrier I4. and one or the other of the erasers 86 carried by the carrier may be substituted for the other simply by sliding the sleeve 92 upwardly along the tubular body I0 so as to clear the slots I6. After having thus cleared the slots, the only other operation that becomes necessary is to Withdraw the pin I8 from the recess or socket and swing the carrier into a reverse position after which the pin may be re-entered into the recess 80 in the opposite arm of the carrier and the sleeve 92 returned to its original position.

While in the foregoing there has been shown and described the preferred embodiment of this invention, it is to be understood that minor changes in the details of construction, combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as claimed.

Having described the invention, what is claimed as new is:

l. A power driven oscillating eraser comprising an elongated tubular body, a rocker arm supported in said body to oscillate about an axis which lies perpendicular to the longitudinal axis of said body, an eraser supported on the rocker arm for movement therewith beyond one end of the tubular body, means at the opposite end of the tubular body and connected to the rocker arm for imparting oscillatory motion thereto, and a 1 pneumatic governor on the body and connected to the rocker arm to reduce the rapidity with which the rocker arm oscillates.

2. A power driven oscillating eraser comprising an elongated tubular body, a rocker arm supported in said body to oscillate about an axis which lies perpendicular to the longitudinal axis of said body, an eraser supported on the rocker arm for movement therewith beyond one end of the tubular body, a spring loaded drum rotatably supported adjacent the end of the body remote from that through which the eraser operates, a roll of tape mounted near the drum, one end of the tape being connected to the drum for winding thereon under the influence of the spring therein, said tape havin a zig-zag longitudinal cam track therein and means on the rocker arm for engaging th cam track and oscillating the arm as the tape is wound upon the drum.

3. A power driven oscillating eraser comprising an elongated tubular body, a rocker arm supported in said body to oscillate about an axis which lies perpendicular to the longitudinal axis of said body, an eraser supported on the rocker arm for movement therewith beyond one end of the tubular body, a spring loaded drum rotatably supported adjacent the end of the body remote from that through which the eraser operates, a roll of tape mounted near the drum, one end of the tape being connected to the drum for winding thereon under the influence of the spring therein, said tape having a zig-zag longitudinal cam track therein, means on the rocker arm for engaging the cam track and oscillating the arm as the tape is wound upon the drum, and means detachably supported on the tubular body adjacent the drum upon which the roll of tape is supported for unreeling said tape from said drum to tension said spring.

4. A power driven oscillating eraser comprising an elongated tubular body, a pivot mounted intermediate the ends of the body for adjustment longitudinally thereof, a rocker arm mounted on the pivot for oscillatory motion within the body, an eraser carrier on one end of the rocker arm for movement therewith beyond one end of the body, a spring loaded drum rotatably supported adjacent the end of the body remote from the eraser, a tape connected at one end to the drum for winding thereon under the influence of the spring contained in said drum, said tape having a zig-zag longitudinal cam track therein and means on the rocker arm for engaging the cam track and oscillating the arm as the tap is wound upon the drum.

5. A power driven oscillating eraser comprising an elongated tubular body, a rocker arm supported in said bod to oscillate about an axis which 1ies perpendicular to the longitudinal axis of said body, an eraser supported on the rocker arm for movement therewith beyond one end of the tubular body, a spring loaded drum rotatably supported adjacent the end of the body remote from that through which the eraser operates, a roll of tape mounted near the drum, one end of the tape being connected to the drum for winding thereon under the influence of the spring therein, said tape having a zig-za longitudinal cam track therein, means on the rocker arm for engaging the cam track and oscillating the arm as the tape is wound upon the drum, and a reel detachably supported adjacent the body upon which the tape is stored prior to its Winding upon the drum.

6. A power driven oscillating eraser comprising an elongated tubular body having diametrically opposed rows of longitudinally spaced aligned openings extending therethrough, an elongated rocker arm within said tubular body, said rocker arm having a longitudinal row of longitudinally spaced openings therein which align with the openings in the tubular body, an eraser carried by one end of said rocker arm and movable in, an are without said tubular body adjacent one end thereof, means carried by the body and connected with the rocker arm adjacent the end thereof remote from the eraser to oscillate said rocker arm within said tubular body and a pivot pin removably entering one group of aligned openings in the body and rocker arm rockably to support the rocker arm in said body, said pivot pins being adapted to be moved to another row of openings to vary the amplitude of movement of the eraser.

7. A power driven oscillating eraser comprising an elongated tubular body, a rocker arm supported in said body to oscillate about an axis which lies perpendicular to the longitudinal axis of said body, an eraser supported on the rocker arm for movement therewith beyond one end of the tubular body, means at the opposite end of the tubular body and connected to the rocker arm for imparting oscillatory motion thereto, a cylinder carried by the tubular body, a piston working within said cylinder and connected to the rocker arm, and heads carried by and closing opposite ends thereof to confine air therein and retard the speed at which the rocker arm oscillates.

PAUL C. HUTTON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,163,018 Bernier June 20, 1939 2,343,237 McElroy Mar. 7, 1944 FOREIGN PATENTS Number Country Date 110,658 Germany May 17, 1900 

